blob: 9ac7b651351bb28d3844f688036ae73348e686a6 [file] [log] [blame]
/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
namespace android {
// T is FastMixer or FastCapture
template<typename T> class AutoPark {
public:
// Park the specific FastThread, which can be nullptr, in hot idle if not currently idling
explicit AutoPark(const sp<T>& fastThread) : mFastThread(fastThread)
{
mPreviousCommand = FastThreadState::HOT_IDLE;
if (fastThread != nullptr) {
auto sq = mFastThread->sq();
FastThreadState *state = sq->begin();
if (!(state->mCommand & FastThreadState::IDLE)) {
mPreviousCommand = state->mCommand;
state->mCommand = FastThreadState::HOT_IDLE;
sq->end();
sq->push(sq->BLOCK_UNTIL_ACKED);
} else {
sq->end(false /*didModify*/);
}
}
}
// Remove the FastThread from hot idle if necessary
~AutoPark()
{
if (!(mPreviousCommand & FastThreadState::IDLE)) {
ALOG_ASSERT(mFastThread != nullptr);
auto sq = mFastThread->sq();
FastThreadState *state = sq->begin();
ALOG_ASSERT(state->mCommand == FastThreadState::HOT_IDLE);
state->mCommand = mPreviousCommand;
sq->end();
sq->push(sq->BLOCK_UNTIL_PUSHED);
}
}
private:
const sp<T> mFastThread;
// if !&IDLE, holds the FastThread state to restore after new parameters processed
FastThreadState::Command mPreviousCommand;
}; // class AutoPark
} // namespace